Adolph f



A. F. HAMACEK.

SHIP.

APPLICATION FILED SEPT. 21. |919.

Patented Feb. 7, 1922.

2 SHEETS-SHEET l.

A. F. HAMACEK. SHIP.

APPLICATION FILED SEPT. 27| 1919.

Patented Feb. 7, 1922.

2 SHEETS-SHEET 2.

ADOLII-I F. HAMACEK, F CHICAGO, ILLINOIS.

SHIP.

Specication of Letters Patent.

Patented Feb. '7, 1922.

Application ledlseptember 27, 1919. VSerial No. 326,724.

To' all whom it may concern.'

Be it known that I, ADoLrH F.` HAMACEK, a citizen of the United States, and a resident of the city of Chicago, county of Cook and State of Illinois, have invented certain new and useful Improvements in Ships, of which the followin is a specification.

My invention relates to improvements in ships, and more especially to the contour of the hull thereof. A ship floating upon the water displaces a certain quantity thereof, and thus forms a cavity or hole in the water to correspond. As the ship moves forwardly through the water, the bow portion thereof is constantly displacing the water at the forward end of this cavity, and substantially an equal quantity of water is constantly flowing into this cavity from the bottom and sides thereof at the rear. If the draft, width and forward speed of the ship are great enough, the aft or stern portion of the ship tends to run out of the water cavity faster than the water runs in, thus tending to Ylose the water pressure and possibly create a vacuum at the rear which retards the forward progress of the ship. The water flowing into the water cavity at the rear possesses substantially the same amount of potential energy that it took to displace Ian equal volume at the bow, so that if this potential energy is uti- -lized and the formation of a vacuum prevented, the shipwill move through the water with little or no resistance, except skin friction. The object of my invention is to provide a ship hull having a cont-our throughout the aft or stern portion thereof, designed and adapted to utilize the potential energy of the water flowing into the water cavity at the rear and also to prevent the formationv of a vacuum.

Other objects will appear hereinafter.

The invention consists in the combination and arrangements hereinafter described and claimed.

The invention will be'best understood by reference to the accompanying drawings forming a part of this specification, and in which,

Fig. 1 is a side view of the aft portion of the hull of a ship, embodying the invention,

Fig. 2,'a top view of the same,

Fig. 8, a rear-end view of the same,

Fig. 4 is a cross-section of the same through line 6, and midship of Fig. 1, and Figs. 5, 6, 7, and 8 are cross-sections of the modified design, and Fig. 9 is a crosssection of the same through midship. The dotted curved line of Fig. 6 shows still another possibility of design in the form of contour.

The hull has a freeboard 10 and submerged lower and upper side portions 11 and 12 forming water channels which merge into a straight midship section adjacent the bilge and terminate respectively aft at the line 2 and at the stern, the portions 12 of each side merging into each other aft of the line 2.

As will bevseen from Fig. 3 the transverse lines ofthe upper surfaces of the channels are straight and swing gradually from the vertical amidships to approximately horizontal at the stern and the transverse lines of the lower surfaces gradually become straighter and become vertical at the stern line 2.

The bottom lines curve inward and rearward to the line 2 and the contour of some or all of the transverse section lines 2 to 8 from the lower line of the freeboard to the bottom of the hull is in the form of an inwardly extending angle or curve, the latter form being shown in Fig. 8. The angularity or degree of curvature also may vary depending on the draft, width and speed of the ship. This angularity results in a slope upwardly and inwardly of the upper underwater portion 12 along the line 13 (Figs. 1 and 3) and the length, slope and contour of this line 13.1nay vary as indicated with the draft, width and speed of the ship.

Obviously, the greater' the draft of the ship and consequently the depth of the water cavity, the longer the time required for the upward flow of the water to lill the vacated portion of the cavity. The width of the ship also has an iniuence on this, but to a lesser extent, inasmuch as the greater the width, the greater the area of upward flow, but of course, there is always some inward flow from the sides of the cavity. This determination is also directly dependent Y of the water from the sides.

upon the forward speed of the ship, and the slope of the aft hull profile, inasmuch as it is the forward speed of the ship which determines the time permitted for the inflow of the water to establish efficient impact and also to prevent the formation of a vacuum. Obviously, then, the greater the draft of the ship and the greater the forward speed thereof, the more gentle must be theupward and inward slope of the portion 12 of the underwater hull. The portion 12 of the hull of the ship is given a gentle upward, side and inward inclination or slope, dependent upon these conditions, and in this way, efficient impact of the inlowing water's obtained thereon. Owing to the slope thus provided, this impact of the inowing water is converted into a forward thrust on the aft part of the ship, and thus the energy required to displace the water at the bow of the ship is, in a large part, restored tothe ship, and the only energy required for the forward propulsion thereof is that necessary to overcome skin friction and the inevitable efficiency losses in the conversion. The upward slope given to the bottom portion 12 is determined largely, if not entirely, by the slope of the line 13, intersecting between the lower and upper portion of the submerged hull, and with this properly determined as above indicated, a ship may be designed which may be propelled through the water at great speed and comparatively with little resistance.

By observing the crossing broken lines in Fig. 1 and Fig. 2 these lines are numbered from left to right 1 to 8 corresponding with the curved lines in Fi 3 from 1 to 8 thus the profile of the hul at these points can be seen.

The broken curved line at the stern shown in Fig. 1 from point 16 to 17 indicates a curve or natural rise of the water following the receding ship at certain speed of the ship. However the inrush of the water is impeded due tc the pressure on the hull, so in order to facilitate the inrush. of the water so as to secure as near as possible full pressure on the aft part of the hull the line 13 is substituted which is of low enough slope to permit the water to fill the gap without undue loss. Also when the length of the line 13 is limited, the slope can be altered to suit the circumstances by raising or lowering this line between the two points 14 and 15.

In Fig. 2 the broken curved lines 11 show the curvature of the lower portion of the under water hull. This curvature on the profile of the hull accommodates the inrush Starting at the cross broken line 8, the water commences to fiow inward from no motion gradually and thence gaining motion towards the broken line 4 thence diminishing in motion to no motion at the line 2, in that way diverting the force of the inrush of the water on the hull of a ship and producing most efcient forward thrust upon the running ship.

In the form of invention shown in Figs. 5, 6 and 7 the lower part of the underwater portion 12 corresponding to portion 12 in Fi s. 1, 2 and 3 is always horizontal instead o swinging to a horizontal from a vertical position as in Figs. 1, 2 and 3.

The portions 12 in this form merely increase in width and form a single Hat stern aft of the section line 2.l

The section lines in the underwater portion 11 in this form are vertical but all lines of sections 11 and 12 are properly faired or curved into each other and into the bottom and freeboard respectively if desired.

These illustrations show how readily the principle of this ship hull profile invention can be applied to all sorts of forms of ship hull aft proles.

`While I have illustrated and described the preferred form of outboard profile of the ship hull for carrying myy invention into effect, this is capable of variation and modification without departing from the spirit of the invention. I, therefore, do not wish to be limited to the precise details of construction set forth, but desire to avail myself of such variations and modifications as come within the scope of the appended claims.

Having described my invention, what I claim as new and desire to secure by Letters .Patent is y" l. A ships form in which an upwardly and inwardly extending water channel Vis formed on each side of the hull from substantially the midship section adjacent the bilge to a point adjacent the stern at both of which points thesaid channelsterminate,

said channels having upper and lower sury faces.

2. A form according to claim 1 whereinl the upper surfaces of the channels are continued aft under the stern.

A form according to claim 2 wherein y.

`ually become straighter and vertical at th stern.

5. A form according to claim l wherein the upper surfaces of the water channels meet thefreeboard at the water line.

6. A form according to claim l wherein In testimony that I claim the foregoing the shps bottom is Hat. as my own, I have hereto affixed my slgna- 7. A ships form according to claim l ture in the presence of two Witnesses. A in which the line of the water channels from ADOLPI-I F. HAMACEK.

5 the blge to the stern is designed in accord- Witnesses:

ance with the draft, Width and speed of VERNER HAMACEK, the vessel. MAX HoNGALTz. 

